A known process for regulating the temperature in the passenger space of a vehicle uses an air conditioning device in which a refrigerant circulates in a univocal manner between an evaporator where it receives heat from a flow of air and a condenser where it yields heat to a flow of air. In this known process, when it is wished to cool a flow of air before it is conveyed into a passenger space, it is brought into contact with the evaporator.
On the other hand, when it is wished to heat a flow of air before conveying it into the passenger space, the heat emitted by the thermal driving engine of the vehicle is normally used for this purpose.
In the case of an electric vehicle, the heat produced by the electrical driving system is not adequate, in winter, to meet the heating requirements of the passenger space. It is therefore necessary to provide an auxiliary source of heat.
The object of the invention is to utilize, for the heating of the passenger space, the existing air conditioning appliance, without altering the direction of circulation of the refrigerant.